Posting from my phone and I don't have LabVIEW but the basic idea is to find a function in the driver (or the command in the manual) to set the source and not use that configure sweep function. You could use the Ramp function to create an array of source values. This array gets passed to the 'set source' function inside a for loop. A single point read would also be inside the loop. The result would be wired to a chart.
This is going to be slower than using the built-in sweep function and you are going to have to write much of the code yourself. What is the problem with just letting the instrument perform the measurement that it is designed to do? You will get the same data when the sweep is complete and you really don't get any additional information by seeing the result point-by-point.
